Devices supporting Process Address Space Identifiers
(PASIDs) can use an IOMMU to access multiple IO address
spaces at the same time. A PCIe device indicates support for
this feature by implementing the PASID capability. This
patch adds support for the capability to the Linux kernel.
Reviewed-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Implement the necessary functions to handle PRI capabilities
on PCIe devices. With PRI devices behind an IOMMU can signal
page fault conditions to software and recover from such
faults.
Reviewed-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

ATS does not depend on IOV support, so move the code into
its own file. This file will also include support for the
PRI and PASID capabilities later.
Also give ATS its own Kconfig variable to allow selecting it
without IOV support.
Reviewed-by: NBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

I originally submitted a patch to workaround this by pushing all Ejection
Requests and Device Checks onto the kacpi_hotplug queue.

http://marc.info/?l=linux-acpi&m=131678270930105&w=2

The patch is still insufficient in that Bus Checks also need to be added.

Rather than add all events, including non-PCI-hotplug events, to the
hotplug queue, mjg suggested that a better approach would be to modify
the acpiphp driver so only acpiphp events would be added to the
kacpi_hotplug queue.

It's a longer patch, but at least we maintain the benefit of having separate
queues in ACPI.  This, of course, is still only a workaround the problem.
As Bjorn and mjg pointed out, we have to refactor a lot of this code to do
the right thing but at this point it is a better to have this code working.

The acpi core places all events on the kacpi_notify queue.  When the acpiphp
driver is loaded and a PCI card with a PCI-to-PCI bridge is removed the
following call sequence occurs:

cleanup_p2p_bridge()
	    -> cleanup_bridge()
		    -> acpi_remove_notify_handler()
			    -> acpi_os_wait_events_complete()
				    -> flush_workqueue(kacpi_notify_wq)

which is the queue we are currently executing on and the process will hang.

Move all hotplug acpiphp events onto the kacpi_hotplug workqueue.  In
handle_hotplug_event_bridge() and handle_hotplug_event_func() we can simply
push the rest of the work onto the kacpi_hotplug queue and then avoid the
deadlock.
Signed-off-by: NPrarit Bhargava <prarit@redhat.com>
Cc: mjg@redhat.com
Cc: bhelgaas@google.com
Cc: linux-acpi@vger.kernel.org
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

The land of PCI power management is a land of sorrow and ugliness,
especially in the area of signaling events by devices.  There are
devices that set their PME Status bits, but don't really bother
to send a PME message or assert PME#.  There are hardware vendors
who don't connect PME# lines to the system core logic (they know
who they are).  There are PCI Express Root Ports that don't bother
to trigger interrupts when they receive PME messages from the devices
below.  There are ACPI BIOSes that forget to provide _PRW methods for
devices capable of signaling wakeup.  Finally, there are BIOSes that
do provide _PRW methods for such devices, but then don't bother to
call Notify() for those devices from the corresponding _Lxx/_Exx
GPE-handling methods.  In all of these cases the kernel doesn't have
a chance to receive a proper notification that it should wake up a
device, so devices stay in low-power states forever.  Worse yet, in
some cases they continuously send PME Messages that are silently
ignored, because the kernel simply doesn't know that it should clear
the device's PME Status bit.

This problem was first observed for "parallel" (non-Express) PCI
devices on add-on cards and Matthew Garrett addressed it by adding
code that polls PME Status bits of such devices, if they are enabled
to signal PME, to the kernel.  Recently, however, it has turned out
that PCI Express devices are also affected by this issue and that it
is not limited to add-on devices, so it seems necessary to extend
the PME polling to all PCI devices, including PCI Express and planar
ones.  Still, it would be wasteful to poll the PME Status bits of
devices that are known to receive proper PME notifications, so make
the kernel (1) poll the PME Status bits of all PCI and PCIe devices
enabled to signal PME and (2) disable the PME Status polling for
devices for which correct PME notifications are received.
Tested-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

The "powernv" platform of the powerpc architecture needs to assign PCI
resources using a specific algorithm to fit some HW constraints of
the IBM "IODA" architecture (related to the ability to create error
handling domains that encompass specific segments of MMIO space).

For doing so, it wants to call pci_setup_bridge() from architecture
specific resource management in order to configure bridges after all
resources have been assigned. So make it non-static.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

These will be shared between the sfc driver and a PCI quirk.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Add the ability to disable PCI-E MPS turning and using the BIOS
configured MPS defaults.  Due to the number of issues recently
discovered on some x86 chipsets, make this the default behavior.

Also, add the option for peer to peer DMA MPS configuration.  Peer to
peer DMA is outside the scope of this patch, but MPS configuration could
prevent it from working by having the MPS on one root port different
than the MPS on another.  To work around this, simply make the system
wide MPS the smallest possible value (128B).
Signed-off-by: NJon Mason <mason@myri.com>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

David reported:

  Attached below is a watered-down version of rt/tst-cpuclock2.c from
  GLIBC.  Just build it with "gcc -o test test.c -lpthread -lrt" or
  similar.

  Run it several times, and you will see cases where the main thread
  will measure a process clock difference before and after the nanosleep
  which is smaller than the cpu-burner thread's individual thread clock
  difference.  This doesn't make any sense since the cpu-burner thread
  is part of the top-level process's thread group.

  I've reproduced this on both x86-64 and sparc64 (using both 32-bit and
  64-bit binaries).

  For example:

  [davem@boricha build-x86_64-linux]$ ./test
  process: before(0.001221967) after(0.498624371) diff(497402404)
  thread:  before(0.000081692) after(0.498316431) diff(498234739)
  self:    before(0.001223521) after(0.001240219) diff(16698)
  [davem@boricha build-x86_64-linux]$ 

  The diff of 'process' should always be >= the diff of 'thread'.

  I make sure to wrap the 'thread' clock measurements the most tightly
  around the nanosleep() call, and that the 'process' clock measurements
  are the outer-most ones.

  ---
  #include <unistd.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <time.h>
  #include <fcntl.h>
  #include <string.h>
  #include <errno.h>
  #include <pthread.h>

  static pthread_barrier_t barrier;

  static void *chew_cpu(void *arg)
  {
	  pthread_barrier_wait(&barrier);
	  while (1)
		  __asm__ __volatile__("" : : : "memory");
	  return NULL;
  }

  int main(void)
  {
	  clockid_t process_clock, my_thread_clock, th_clock;
	  struct timespec process_before, process_after;
	  struct timespec me_before, me_after;
	  struct timespec th_before, th_after;
	  struct timespec sleeptime;
	  unsigned long diff;
	  pthread_t th;
	  int err;

	  err = clock_getcpuclockid(0, &process_clock);
	  if (err)
		  return 1;

	  err = pthread_getcpuclockid(pthread_self(), &my_thread_clock);
	  if (err)
		  return 1;

	  pthread_barrier_init(&barrier, NULL, 2);
	  err = pthread_create(&th, NULL, chew_cpu, NULL);
	  if (err)
		  return 1;

	  err = pthread_getcpuclockid(th, &th_clock);
	  if (err)
		  return 1;

	  pthread_barrier_wait(&barrier);

	  err = clock_gettime(process_clock, &process_before);
	  if (err)
		  return 1;

	  err = clock_gettime(my_thread_clock, &me_before);
	  if (err)
		  return 1;

	  err = clock_gettime(th_clock, &th_before);
	  if (err)
		  return 1;

	  sleeptime.tv_sec = 0;
	  sleeptime.tv_nsec = 500000000;
	  nanosleep(&sleeptime, NULL);

	  err = clock_gettime(th_clock, &th_after);
	  if (err)
		  return 1;

	  err = clock_gettime(my_thread_clock, &me_after);
	  if (err)
		  return 1;

	  err = clock_gettime(process_clock, &process_after);
	  if (err)
		  return 1;

	  diff = process_after.tv_nsec - process_before.tv_nsec;
	  printf("process: before(%lu.%.9lu) after(%lu.%.9lu) diff(%lu)\n",
		 process_before.tv_sec, process_before.tv_nsec,
		 process_after.tv_sec, process_after.tv_nsec, diff);
	  diff = th_after.tv_nsec - th_before.tv_nsec;
	  printf("thread:  before(%lu.%.9lu) after(%lu.%.9lu) diff(%lu)\n",
		 th_before.tv_sec, th_before.tv_nsec,
		 th_after.tv_sec, th_after.tv_nsec, diff);
	  diff = me_after.tv_nsec - me_before.tv_nsec;
	  printf("self:    before(%lu.%.9lu) after(%lu.%.9lu) diff(%lu)\n",
		 me_before.tv_sec, me_before.tv_nsec,
		 me_after.tv_sec, me_after.tv_nsec, diff);

	  return 0;
  }

This is due to us using p->se.sum_exec_runtime in
thread_group_cputime() where we iterate the thread group and sum all
data. This does not take time since the last schedule operation (tick
or otherwise) into account. We can cure this by using
task_sched_runtime() at the cost of having to take locks.

This also means we can (and must) do away with
thread_group_sched_runtime() since the modified thread_group_cputime()
is now more accurate and would deadlock when called from
thread_group_sched_runtime().

Aside of that it makes the function safe on 32 bit systems. The old
code added t->se.sum_exec_runtime unprotected. sum_exec_runtime is a
64bit value and could be changed on another cpu at the same time.
Reported-by: NDavid Miller <davem@davemloft.net>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: stable@kernel.org
Link: http://lkml.kernel.org/r/1314874459.7945.22.camel@twinsTested-by: NDavid Miller <davem@davemloft.net>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

The IEEE 1588 standard defines two kinds of messages, event and general
messages. Event messages require time stamping, and general do not. When
using UDP transport, two separate ports are used for the two message
types.

The BPF designed to recognize event messages incorrectly classifies L2
general messages as event messages. This commit fixes the issue by
extending the filter to check the message type field for L2 PTP packets.
Event messages are be distinguished from general messages by testing
the "general" bit.
Signed-off-by: NRichard Cochran <richard.cochran@omicron.at>
Cc: <stable@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

That flag no longer makes sense, since we don't look up automount points
as eagerly any more.  Additionally, it turns out that the NO_AUTOMOUNT
handling was buggy to begin with: it would avoid automounting even for
cases where we really *needed* to do the automount handling, and could
return ENOENT for autofs entries that hadn't been instantiated yet.

With our new non-eager automount semantics, one discussion has been
about adding a AT_AUTOMOUNT flag to vfs_fstatat (and thus the
newfstatat() and fstatat64() system calls), but it's probably not worth
it: you can always force at least directory automounting by simply
adding the final '/' to the filename, which works for *all* of the stat
family system calls, old and new.

So AT_NO_AUTOMOUNT (and thus LOOKUP_NO_AUTOMOUNT) really were just a
result of our bad default behavior.
Acked-by: NIan Kent <raven@themaw.net>
Acked-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since we've now turned around and made LOOKUP_FOLLOW *not* force an
automount, we want to add the ability to force an automount event on
lookup even if we don't happen to have one of the other flags that force
it implicitly (LOOKUP_OPEN, LOOKUP_DIRECTORY, LOOKUP_PARENT..)

Most cases will never want to use this, since you'd normally want to
delay automounting as long as possible, which usually implies
LOOKUP_OPEN (when we open a file or directory, we really cannot avoid
the automount any more).

But Trond argued sufficiently forcefully that at a minimum bind mounting
a file and quotactl will want to force the automount lookup.  Some other
cases (like nfs_follow_remote_path()) could use it too, although
LOOKUP_DIRECTORY would work there as well.

This commit just adds the flag and logic, no users yet, though.  It also
doesn't actually touch the LOOKUP_NO_AUTOMOUNT flag that is related, and
was made irrelevant by the same change that made us not follow on
LOOKUP_FOLLOW.

Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Ian Kent <raven@themaw.net>
Cc: Jeff Layton <jlayton@redhat.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Greg KH <gregkh@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If optional discard support in dm-crypt is enabled, discards requests
bypass the crypt queue and blocks of the underlying device are discarded.
For the read path, discarded blocks are handled the same as normal
ciphertext blocks, thus decrypted.

So if the underlying device announces discarded regions return zeroes,
dm-crypt must disable this flag because after decryption there is just
random noise instead of zeroes.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

598841ca ([S390] use gmap address
spaces for kvm guest images) changed kvm on s390 to use a separate
address space for kvm guests. We can now put KVM guests anywhere
in the user address mode with a size up to 8PB - as long as the
memory is 1MB-aligned. This change was done without KVM extension
capability bit.
The change was added after 3.0, but we still have a chance to add
a feature bit before 3.1 (keeping the releases in a sane state).
We use number 71 to avoid collisions with other pending kvm patches
as requested by Alexander Graf.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Acked-by: NAvi Kivity <avi@redhat.com>
Cc: Alexander Graf <agraf@suse.de>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>

irq_domain_simple_ops is exported, but is not declared in irqdomain.h,
so add it.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: marc.zyngier@arm.com
Cc: thomas.abraham@linaro.org
Cc: jamie@jamieiles.com
Cc: b-cousson@ti.com
Cc: shawn.guo@linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: devicetree-discuss@lists.ozlabs.org
Link: http://lkml.kernel.org/r/1316017900-19918-2-git-send-email-robherring2@gmail.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

commit 946cedcc (tcp: Change possible SYN flooding messages)
added a build error if CONFIG_SYN_COOKIES=n
Reported-by: NMarkus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

With the conversion of struct flowi to a union of AF-specific structs, some
operations on the flow cache need to account for the exact size of the key.
Signed-off-by: NDavid Ward <david.ward@ll.mit.edu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

AF-specific flowi structs are now passed to flow_key_compare, which must
also be aligned to a long.
Signed-off-by: NDavid Ward <david.ward@ll.mit.edu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Attempt to reduce the number of IP packets emitted in response to single
SCTP packet (2e3216cd) introduced a complication - if a packet contains
two COOKIE_ECHO chunks and nothing else then SCTP state machine corks the
socket while processing first COOKIE_ECHO and then loses the association
and forgets to uncork the socket. To deal with the issue add new SCTP
command which can be used to set association explictly. Use this new
command when processing second COOKIE_ECHO chunk to restore the context
for SCTP state machine.
Signed-off-by: NMax Matveev <makc@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

dev_forward_skb loops an skb back into host networking
stack which might hang on the memory indefinitely.
In particular, this can happen in macvtap in bridged mode.
Copy the userspace fragments to avoid blocking the
sender in that case.

As this patch makes skb_copy_ubufs extern now,
I also added some documentation and made it clear
the SKBTX_DEV_ZEROCOPY flag automatically instead
of doing it in all callers. This can be made into a separate
patch if people feel it's worth it.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

"Possible SYN flooding on port xxxx " messages can fill logs on servers.

Change logic to log the message only once per listener, and add two new
SNMP counters to track :

TCPReqQFullDoCookies : number of times a SYNCOOKIE was replied to client

TCPReqQFullDrop : number of times a SYN request was dropped because
syncookies were not enabled.

Based on a prior patch from Tom Herbert, and suggestions from David.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
CC: Tom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Building a kernel with hotplug disabled results in a link failure:

  `bgpio_remove' referenced in section `___ksymtab_gpl+bgpio_remove' of drivers/built-in.o: defined in discarded section `.devexit.text' of drivers/built-in.o

This is because of bgpio_remove() is exported.  It is illegal to export
symbols which are discarded either at link time or as part of an
init/exit section.

Fix this by dropping the __devexit attributation from bgpio_remove().
Also drop the __devinit attributation from bgpio_init().
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Revert the post-3.0 commit 82f9d486 ("memcg: add
memory.vmscan_stat").

The implementation of per-memcg reclaim statistics violates how memcg
hierarchies usually behave: hierarchically.

The reclaim statistics are accounted to child memcgs and the parent
hitting the limit, but not to hierarchy levels in between.  Usually,
hierarchical statistics are perfectly recursive, with each level
representing the sum of itself and all its children.

Since this exports statistics to userspace, this may lead to confusion
and problems with changing things after the release, so revert it now,
we can try again later.
Signed-off-by: NJohannes Weiner <jweiner@redhat.com>
Acked-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Ying Han <yinghan@google.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix kernel-doc warning about internal/private data by marking it
as "private:" so that kernel-doc will ignore it.

  Warning(include/linux/regulator/consumer.h:128): No description found for parameter 'ret'
Signed-off-by: NRandy Dunlap <rdunlap@xenotime.net>
Acked-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix kernel-doc warning in net/cfg80211.h:

  Warning(include/net/cfg80211.h:1884): No description found for parameter 'registered'
Signed-off-by: NRandy Dunlap <rdunlap@xenotime.net>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This needs to be an out of band value for the register and on this device
registers are 16 bit so we must shift left one to the 17th bit.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@kernel.org
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Signed-off-by: NJim Garlick <garlick@llnl.gov>
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

Some of the flags are OS/arch dependent we add a 9p
protocol value which maps to asm-generic/fcntl.h values in Linux
Based on the original patch from Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

Save inode->dirtied_when in the raw trace output for reliable scripting,
and to also show in formatted output the relative age in seconds for
easy human reading.

CC: Jan Kara <jack@suse.cz>
Acked-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NWu Fengguang <fengguang.wu@intel.com>

Allow transparent sockets to be less restrictive about
the source ip of ipv6 udp packets being sent.

Google-Bug-Id: 5018138
Signed-off-by: NMaciej Żenczykowski <maze@google.com>
CC: "Erik Kline" <ek@google.com>
CC: "Lorenzo Colitti" <lorenzo@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The current cgroup context switch code was incorrect leading
to bogus counts. Furthermore, as soon as there was an active
cgroup event on a CPU, the context switch cost on that CPU
would increase by a significant amount as demonstrated by a
simple ping/pong example:

 $ ./pong
 Both processes pinned to CPU1, running for 10s
 10684.51 ctxsw/s

Now start a cgroup perf stat:
 $ perf stat -e cycles,cycles -A -a -G test  -C 1 -- sleep 100

$ ./pong
 Both processes pinned to CPU1, running for 10s
 6674.61 ctxsw/s

That's a 37% penalty.

Note that pong is not even in the monitored cgroup.

The results shown by perf stat are bogus:
 $ perf stat -e cycles,cycles -A -a -G test  -C 1 -- sleep 100

 Performance counter stats for 'sleep 100':

 CPU1 <not counted> cycles   test
 CPU1 16,984,189,138 cycles  #    0.000 GHz

The second 'cycles' event should report a count @ CPU clock
(here 2.4GHz) as it is counting across all cgroups.

The patch below fixes the bogus accounting and bypasses any
cgroup switches in case the outgoing and incoming tasks are
in the same cgroup.

With this patch the same test now yields:
 $ ./pong
 Both processes pinned to CPU1, running for 10s
 10775.30 ctxsw/s

Start perf stat with cgroup:

 $ perf stat -e cycles,cycles -A -a -G test  -C 1 -- sleep 10

Run pong outside the cgroup:
 $ /pong
 Both processes pinned to CPU1, running for 10s
 10687.80 ctxsw/s

The penalty is now less than 2%.

And the results for perf stat are correct:

$ perf stat -e cycles,cycles -A -a -G test  -C 1 -- sleep 10

 Performance counter stats for 'sleep 10':

 CPU1 <not counted> cycles test #    0.000 GHz
 CPU1 23,933,981,448 cycles      #    0.000 GHz

Now perf stat reports the correct counts for
for the non cgroup event.

If we run pong inside the cgroup, then we also get the
correct counts:

$ perf stat -e cycles,cycles -A -a -G test  -C 1 -- sleep 10

 Performance counter stats for 'sleep 10':

 CPU1 22,297,726,205 cycles test #    0.000 GHz
 CPU1 23,933,981,448 cycles      #    0.000 GHz

      10.001457237 seconds time elapsed
Signed-off-by: NStephane Eranian <eranian@google.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110825135803.GA4697@quadSigned-off-by: NIngo Molnar <mingo@elte.hu>

The nfsservctl system call is now gone, so we should remove all
linkage for it.
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We need a callback to do some things after pwm_enable, pwm_disable
and pwm_config.
Signed-off-by: NDilan Lee <dilee@nvidia.com>
Reviewed-by: NRobert Morell <rmorell@nvidia.com>
Reviewed-by: NArun Murthy <arun.murthy@stericsson.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Replace/remove use of RIO v.1.2 registers/bits that are not
forward-compatible with newer versions of RapidIO specification.

RapidIO specification v.1.3 removed Write Port CSR, Doorbell CSR,
Mailbox CSR and Mailbox and Doorbell bits of the PEF CAR.

Use of removed (since RIO v.1.3) register bits affects users of
currently available 1.3 and 2.x compliant devices who may use not so
recent kernel versions.

Removing checks for unsupported bits makes corresponding routines
compatible with all versions of RapidIO specification.  Therefore,
backporting makes stable kernel versions compliant with RIO v.1.3 and
later as well.
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Chul Kim <chul.kim@idt.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NEvgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Purely in-memory filesystems do not use the inode hash as the dcache
tells us if an entry already exists.  As a result, they do not call
unlock_new_inode, and thus directory inodes do not get put into a
different lockdep class for i_sem.

We need the different lockdep classes, because the locking order for
i_mutex is different for directory inodes and regular inodes.  Directory
inodes can do "readdir()", which takes i_mutex *before* possibly taking
mm->mmap_sem (due to a page fault while copying the directory entry to
user space).

In contrast, regular inodes can be mmap'ed, which takes mm->mmap_sem
before accessing i_mutex.

The two cases can never happen for the same inode, so no real deadlock
can occur, but without the different lockdep classes, lockdep cannot
understand that.  As a result, if CONFIG_DEBUG_LOCK_ALLOC is set, this
can lead to false positives from lockdep like below:

    find/645 is trying to acquire lock:
     (&mm->mmap_sem){++++++}, at: [<ffffffff81109514>] might_fault+0x5c/0xac

    but task is already holding lock:
     (&sb->s_type->i_mutex_key#15){+.+.+.}, at: [<ffffffff81149f34>]
    vfs_readdir+0x5b/0xb4

    which lock already depends on the new lock.

    the existing dependency chain (in reverse order) is:

    -> #1 (&sb->s_type->i_mutex_key#15){+.+.+.}:
          [<ffffffff8108ac26>] lock_acquire+0xbf/0x103
          [<ffffffff814db822>] __mutex_lock_common+0x4c/0x361
          [<ffffffff814dbc46>] mutex_lock_nested+0x40/0x45
          [<ffffffff811daa87>] hugetlbfs_file_mmap+0x82/0x110
          [<ffffffff81111557>] mmap_region+0x258/0x432
          [<ffffffff811119dd>] do_mmap_pgoff+0x2ac/0x306
          [<ffffffff81111b4f>] sys_mmap_pgoff+0x118/0x16a
          [<ffffffff8100c858>] sys_mmap+0x22/0x24
          [<ffffffff814e3ec2>] system_call_fastpath+0x16/0x1b

    -> #0 (&mm->mmap_sem){++++++}:
          [<ffffffff8108a4bc>] __lock_acquire+0xa1a/0xcf7
          [<ffffffff8108ac26>] lock_acquire+0xbf/0x103
          [<ffffffff81109541>] might_fault+0x89/0xac
          [<ffffffff81149cff>] filldir+0x6f/0xc7
          [<ffffffff811586ea>] dcache_readdir+0x67/0x205
          [<ffffffff81149f54>] vfs_readdir+0x7b/0xb4
          [<ffffffff8114a073>] sys_getdents+0x7e/0xd1
          [<ffffffff814e3ec2>] system_call_fastpath+0x16/0x1b

This patch moves the directory vs file lockdep annotation into a helper
function that can be called by in-memory filesystems and has hugetlbfs
call it.
Signed-off-by: NJosh Boyer <jwboyer@redhat.com>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I ran into a couple of programs which broke with the new Linux 3.0
version.  Some of those were binary only.  I tried to use LD_PRELOAD to
work around it, but it was quite difficult and in one case impossible
because of a mix of 32bit and 64bit executables.

For example, all kind of management software from HP doesnt work, unless
we pretend to run a 2.6 kernel.

  $ uname -a
  Linux svivoipvnx001 3.0.0-08107-g97cd98f #1062 SMP Fri Aug 12 18:11:45 CEST 2011 i686 i686 i386 GNU/Linux

  $ hpacucli ctrl all show

  Error: No controllers detected.

  $ rpm -qf /usr/sbin/hpacucli
  hpacucli-8.75-12.0

Another notable case is that Python now reports "linux3" from
sys.platform(); which in turn can break things that were checking
sys.platform() == "linux2":

  https://bugzilla.mozilla.org/show_bug.cgi?id=664564

It seems pretty clear to me though it's a bug in the apps that are using
'==' instead of .startswith(), but this allows us to unbreak broken
programs.

This patch adds a UNAME26 personality that makes the kernel report a
2.6.40+x version number instead.  The x is the x in 3.x.

I know this is somewhat ugly, but I didn't find a better workaround, and
compatibility to existing programs is important.

Some programs also read /proc/sys/kernel/osrelease.  This can be worked
around in user space with mount --bind (and a mount namespace)

To use:

  wget ftp://ftp.kernel.org/pub/linux/kernel/people/ak/uname26/uname26.c
  gcc -o uname26 uname26.c
  ./uname26 program
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Cleaning up the code a little bit. attempt_plug_merge() traverses the plug
list anyway, we can do the request counting there, so stack size is reduced
a little bit.
The motivation here is I suspect if we should count the requests for each
queue (task could handle multiple disks in the meantime), but my test doesn't
show it's worthy doing. If somebody proves we should do it, below change
will make that more easier.
Signed-off-by: NShaohua Li <shli@kernel.org>
Signed-off-by: NShaohua Li <shaohua.li@intel.com>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

tty_operations->remove is normally called like:
queue_release_one_tty
 ->tty_shutdown
   ->tty_driver_remove_tty
     ->tty_operations->remove

However tty_shutdown() is called from queue_release_one_tty() only if
tty_operations->shutdown is NULL. But for pty, it is not.
pty_unix98_shutdown() is used there as ->shutdown.

So tty_operations->remove of pty (i.e. pty_unix98_remove()) is never
called. This results in invalid pty_count. I.e. what can be seen in
/proc/sys/kernel/pty/nr.

I see this was already reported at:
  https://lkml.org/lkml/2009/11/5/370
But it was not fixed since then.

This patch is kind of a hackish way. The problem lies in ->install. We
allocate there another tty (so-called tty->link). So ->install is
called once, but ->remove twice, for both tty and tty->link. The fix
here is to count both tty and tty->link and divide the count by 2 for
user.

And to have ->remove called, let's make tty_driver_remove_tty() global
and call that from pty_unix98_shutdown() (tty_operations->shutdown).

While at it, let's document that when ->shutdown is defined,
tty_shutdown() is not called.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: stable <stable@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Add a new REQ_PRIO to let requests preempt others in the cfq I/O schedule,
and lave REQ_META purely for marking requests as metadata in blktrace.

All existing callers of REQ_META except for XFS are updated to also
set REQ_PRIO for now.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NNamhyung Kim <namhyung@gmail.com>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>